Spruce bark extract as a sun protection agent in sunscreens

This study aimed to clarify the feasibility of utilizing spruce inner bark extract as a sun protection agent in sunscreens. Ultrasound-assisted extraction with 60 v-% ethanol was applied to isolate the extract in 25-30 % yield, that was almost independent of the temperature (45-75 oC) and time (5-60 min) of the treatment. However, the yield of stilbene glucosides, measured by UV absorption spectroscopy, was highest after ca. 20 min extraction. Nuclear magnetic resonance spectroscopy of the extract showed that it consisted mainly of three stilbene glucosides, astringin, isorhapontin and polydatin (piceid). The maximum overall yield of the stilbene glucosides was > 20 %. Extraction with water gave a much lower yield of the stilbene glucosides. Sunscreens composed of a mixture of vegetable oils, surfactants (fatty acids), glycerin, water and the bark extract were prepared with the low-energy emulsification method. The performance of the sunscreens was assessed by spreading them on a photosensitive paper and observing the change in color during exposure to light. Commercial sunscreens with known SPF values (15-50) were used as references. Addition of 2-5 % of the bark extract in the sunscreen provided similar protection against UV light compared to the commercial products. Use of the spruce inner bark extract as the sun protection agent in sunscreens appeared to be potentially feasible and should be studied further

Effect of solution on the isoelectric point of collagen

The experiment mainly focusing on what kinds of effects collagen have when environment changed, the environment including buffer, pH and ionic nature. Using a variety of testing methods to search collagen’s morphological change, as well as the essential reason that environmental impact to collagen structure, stability, mechanical properties, biological properties(crosslinking effect)

The critical roles and therapeutic implications of tuft cells in cancer

Tuft cells are solitary chemosensory epithelial cells with microvilli at the top, which are found in hollow organs such as the gastrointestinal tract, pancreas, and lungs. Recently, an increasing number of studies have revealed the chemotactic abilities and immune function of the tuft cells, and numerous efforts have been devoted to uncovering the role of tuft cells in tumors. Notably, accumulating evidence has shown that the specific genes (POU2F3, DCLK1) expressed in tuft cells are involved in vital processes related with carcinogenesis and cancer development. However, the interaction between the tuft cells and cancer remains to be further elucidated. Here, based on an introduction of biological functions and specific markers of the tuft cells, we have summarized the functional roles and potential therapeutic implications of tuft cells in cancers, including pancreatic cancer, lung cancer, gastric cancer, colon cancer, and liver cancer, which is in the hope of inspiring the future research in validating tuft cells as novel strategies for cancer therapies

Non-synchronous Structural and Functional Dynamics During the Coalescence of Two Distinct Soil Bacterial Communities

Soil is a unique environment in which the microbiota is frequently subjected to community coalescence. Additions of organic fertilizer and precipitation of dust induce coalescent events in soil. However, the fates of these communities after coalescence remain uncharted. Thus, to explore the effects of microbiota coalescence, we performed reciprocal inoculation and incubation experiments in microcosms using two distinct soils. The soils were, respectively, collected from a cropland and an industrial site, and the reciprocal inoculation was performed as models for the incursion of highly exotic microbiota into the soil. After incubation under either aerobic or anaerobic conditions for two months, the soils were assayed for their bacterial community structure and denitrification function. According to the 16S rRNA gene sequencing results, the inoculated soil showed a significant shift in bacterial community structure after incubation—particularly in the industrial soil. The structures of the bacterial communities changed following the coalescence but were predicted to have the same functional potential, e.g., nitrogen metabolism, as determined by the quantification of denitrifying genes and nitrogen gas production in the inoculated soil samples, which showed values equivalent those in the original recipient soil samples regardless of inoculum used. The functional prediction based on the known genomes of the taxa that shifted in the incubated sample communities indicates that the high functional overlap and redundancy across bacteria acted as a mechanism that preserved all the metabolic functions in the soil. These findings hint at the mechanisms underlying soil biodiversity maintenance and ecosystem function

Constitutive Activation of β-Catenin in Differentiated Osteoclasts Induces Bone Loss in Mice

Background/Aims: Activation of the Wnt/β-catenin signalling pathway has been widely investigated in bone biology and shown to promote bone formation. However, its specific effects on osteoclast differentiation have not been fully elucidated. Our study aimed to identify the role of β-catenin in osteoclastogenesis and bone homeostasis. Methods: In the present study, exon 3 in the β-catenin gene (Ctnnb1) allele encoding phosphorylation target serine/threonine residues was flanked by floxP sequences. We generated mice exhibiting conditional β-catenin activation (Ctsk-Cre;Ctnnb1flox(exon3)/+, designated CA-β-catenin) by crossing Ctnnb1flox(exon3)/flox(exon3) mice with osteoclast-specific Ctsk-Cre mice. Bone growth and bone mass were analysed by micro-computed tomography (micro-CT) and histomorphometry. To further examine osteoclast activity, osteoclasts were induced from bone marrow monocytes (BMMs) isolated from CA-β-catenin and Control mice in vitro. Osteoclast differentiation was detected by tartrate-resistant acid phosphatase (TRAP) staining, immunofluorescence staining and reverse transcription-quantitative PCR (RT–qPCR) analysis. Results: Growth retardation and low bone mass were observed in CA-β-catenin mice. Compared to controls, CA-β-catenin mice had significantly reduced trabecular bone numbers under growth plates as well as thinner cortical bones. Moreover, increased TRAP-positive osteoclasts were observed on the surfaces of trabecular bones and cortical bones in the CA-β-catenin mice; consistent results were observed in vitro. In the CA-β-catenin group, excessive numbers of osteoclasts were induced from BMMs, accompanied by the increased expression of osteoclast-associated marker genes. Conclusion: These results indicated that the constitutive activation of β-catenin in osteoclasts promotes osteoclast formation, resulting in bone loss

Spruce bark stilbenes as a nature-inspired sun blocker for sunscreens

Funding Information: Aalto University CHEMARTS is acknowledged as the initiator of the original concept of applying spruce bark extracts as UV protection additives. The authors would like to thank Petri Widsten (VTT), Owain Dawson and Maria Rodriguez (Aalto University), and Jean-Claude HUBAUD (Helioscience) for their skilful assistance in the UV absorbance measurements. Special thanks go to Heidi Henrickson from Aalto University for the language check. This work is part of the Academy of Finland's Flagship Programme under Project No. 318890 and No. 318891 (Competence Center for Materials Bioeconomy, FinnCERES). Publisher Copyright: © 2022 The Royal Society of ChemistryStilbene glucosides are a class of natural compounds that have been used as natural antioxidants and antifungal and antibacterial agents. Here, spruce bark extract, rich in stilbene glucosides, was used as a natural ultraviolet-protective additive for sunscreens. The ultrasound-assisted extraction of fresh Norway spruce (Picea abies) inner bark with 60% ethanol provided an extract in ca. 25% yield, of which one third consisted of three stilbene glucosides (astringin, isorhapontin and polydatin) which were fully characterized and quantified by 1D and 2D NMR spectroscopy and high resolution-liquid chromatography mass spectrometry (HR-LCMS). Emulsions of the extract were prepared and applied on polymethyl methacrylate (PMMA) plates to study the effect of the extract on UV light absorbance. A 10% emulsion with spruce crude extracts (containing 35% stilbene glucosides) alone provided UV protection equal to half the efficiency of commercial SPF 15 sun lotions, which also displayed a 21-32% higher SPF effect in comparison with the same dosages of alkali lignin nanoparticles using the same sunscreen emulsification process. A preparative scale chromatography was established for the first time as a fast and highly efficient method in the small-scale recovery of stilbene glucosides from spruce inner bark for full structural elucidation and has a good chance to be industrially scalable. Overall, this exploration may launch a new era for the application of stilbene glucosides of spruce bark extracts as genuine replacements for synthetic UV filters, upgrading this underappreciated bark residue from energy production to higher value cosmetic use.Peer reviewe

Impact of Donepezil Supplementation on Alzheimer’s Disease-like Pathology and Gut Microbiome in APP/PS1 Mice

Based on published information, the occurrence and development of Alzheimer’s disease (AD) are potentially related to gut microbiota changes. Donepezil hydrochloride (DH), which enhances cholinergic activity by blocking acetylcholinesterase (AChE), is one of the first-line drugs for AD treatment approved by the Food and Drug Administration (FDA) of the USA. However, the potential link between the effects of DH on the pathophysiological processes of AD and the gut microbiota remains unclear. In this study, pathological changes in the brain and colon, the activities of superoxide dismutase (SOD) and AChE, and changes in intestinal flora were observed. The results showed that Aβ deposition in the prefrontal cortex and hippocampus of AD mice was significantly decreased, while colonic inflammation was significantly alleviated by DH treatment. Concomitantly, SOD activity was significantly improved, while AChE was significantly reduced after DH administration. In addition, the gut microbiota community composition of AD mice was significantly altered after DH treatment. The relative abundance of Akkermansia in the AD group was 54.8% higher than that in the N group. The relative abundance of Akkermansia was increased by 18.3% and 53.8% in the AD_G group and the N_G group, respectively. Interestingly, Akkermansia showed a potential predictive value and might be a biomarker for AD. Molecular docking revealed the binding mode and major forces between DH and membrane proteins of Akkermansia. The overall results suggest a novel therapeutic mechanism for treating AD and highlight the critical role of gut microbiota in AD pathology

The Preparation, Microstructure, and Wet Wear Properties of an Fe55-Based Welding Layer with the Co-Addition of 0.01 wt% CeO₂ and 1.5 wt% SiC Particles Using the Plasma Beam Spraying Method

Severe erosion wear is found on valve spools, which threatens the safety and reliability of these units. The use of the plasma beam spraying surfacing method can significantly improve the corrosion resistance and sealing performance of hydraulic valve spools, reduce material waste, and reduce maintenance costs. The effects of the co-addition of CeO2 and SiC particles on the morphology, surface cracks, microstructure, precipitated phases, and wear property of plasma-beam-sprayed Fe55-based coatings on 1025 steel were investigated using OM, EDS, ultra-deep field microscopy, and a wet sand rubber wheel friction tester, respectively. The dendrite exhibited a directional growth pattern perpendicular to the substrate and the transitional states of the microstructure with the co-addition of CeO2 and SiC particles. CeO2 or SiC reduced the liquid phase diffusion coefficient DL of Cr and C and resulted in a decrease in the G/R ratio. The dendrites changed into equiaxed grains. The main phase composition of the Fe55 welding layer was Cr7C3, γ-Fe. The martensite in the surfacing layer and the carbides formed Cr7C3, which can improve the hardness of the surfacing layer. The grain boundaries consisted mainly of a reticular eutectic structure. The uniform distribution of the Cr7C3 hard phase in the Fe55+1.5 wt% SiC+0.01 wt% CeO2 resulted in a uniformly worn surface. The sub-wear mechanisms during the friction process were micro-ploughing and micro-cutting. The hardness and toughness of Fe55+1.5 wt% SiC+0.01 wt% CeO2 were well-matched, avoiding excessive micro-cutting and microplastic deformation. A low content of CeO2 could lead to the formation of equiaxed grain and effectively improve the uniformity of the microstructure. The wear-resistant layer of Fe55+1.5 wt% SiC+0.01 wt% CeO2 can effectively improve the service life and long-term sealing performance of the valve spools